“I’m no psychology professor but it does seem weird to me that someone could have a selective fear of flying,” he wrote. “Can’t do it to testify but for vacation, well it’s not a problem at all.”

People are criticising the social media post – especially because Ford did fly across the county to testify.

After delivering a powerful opening statement about an alleged sexual assault by Brett Kavanaugh before the Senate Judiciary Committee, Christine Blasey Ford was questioned by senators on the committee and a career prosecutor enlisted by the Republican majority.

Ford, a research psychologist and professor at the University of Palo Alto, was, at one point, asked about her anxiety, specifically her fear of flying, by prosecutor Rachel Mitchell.

The psychology professor told Mitchell that she has anxiety around flying, but she was “able to get up the gumption” to fly across the country from California to Washington, DC, to testify on Thursday. Ford also said she has flown in the past for work trips, family visits, and vacations.

But Donald Trump Jr. took to Twitter, calling Ford’s anxiety into question.

“I’m no psychology professor but it does seem weird to me that someone could have a selective fear of flying,” he wrote. “Can’t do it to testify but for vacation, well it’s not a problem at all.”

I’m no psychology professor but it does seem weird to me that someone could have a selective fear of flying.

Can’t do it to testify but for vacation, well it’s not a problem at all.

Some think Trump’s tweet is a misguided attempt to dismantle Ford’s credibility.

Hey Jackass, If whether Dr Ford has a fear of flying or not is your defence to discredit her, then you are grasping at straws. She is a credible witness, and so say 98% of the responses I've read on twitter. https://t.co/diA1wacpvt